The pthread_barrierattr_destroy() function shall destroy a barrier
attributes object. A destroyed attr attributes object can be
reinitialized using pthread_barrierattr_init(); the results of
otherwise referencing the object after it has been destroyed are undefined. An
implementation may cause pthread_barrierattr_destroy() to set the
object referenced by attr to an invalid value.
The pthread_barrierattr_init() function shall initialize a barrier
attributes object attr with the default value for all of the attributes
defined by the implementation.
Results are undefined if pthread_barrierattr_init() is called specifying
an already initialized attr attributes object.
After a barrier attributes object has been used to initialize one or more
barriers, any function affecting the attributes object (including destruction)
shall not affect any previously initialized barrier.
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html